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Study on Zolpidem's Effects in Patients with Vision Impairments, Disorders of Consciousness, and Neurotypical Volunteers

Verified siteRegistered drugNo placebo
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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on understanding how the medication zolpidem works in different groups of people. The study involves patients with disorders of consciousness, individuals with vision impairments, and neurotypical volunteers, who represent the general population. Some people in these groups have unusual reactions to zolpidem, such as regaining consciousness or temporarily recovering vision. The study aims to explore these unexpected responses to improve personalized care for patients.

The trial will use two medications: zolpidem, which is a film-coated tablet, and mannitol, which is a capsule. Participants will take these medications orally, either by mouth or through a tube if necessary. The study will observe how these medications affect the participants over a short period, with a focus on understanding the unique reactions some people have to zolpidem.

Throughout the study, researchers will monitor various aspects such as consciousness levels, alertness, and cognitive performance. They will also use techniques like high-density electroencephalography (hdEEG) to study brain activity. The findings from this study could lead to better understanding and treatment options for those who experience paradoxical responses to zolpidem.

The research process

The trial runs in 5 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial assessment

    Upon joining the study, an initial assessment will be conducted to establish a baseline clinical profile. This involves observing the participant for at least one week before any intervention begins.

    During this period, various tests and assessments will be performed to understand the participant's current health status and any specific conditions related to the study.

  2. Step 2

    Medication administration

    Participants will receive the study medication, which includes zolpidem in the form of a film-coated tablet. The medication can be taken orally or through a nasogastric or percutaneous endoscopic gastrostomy tube, depending on the participant's needs.

    The dosage of zolpidem is 10 mg, and the frequency and duration of administration will be determined by the study protocol.

  3. Step 3

    Monitoring and assessments

    Throughout the trial, participants will undergo regular monitoring and assessments to evaluate their response to the medication. This includes measuring consciousness levels, alertness, sleepiness, cognitive performance, and neural complexity.

    For participants with vision impairments, additional ophthalmological testing will be conducted to assess any changes in visual functions.

  4. Step 4

    Phenomenological experiences

    Participants may be asked to share their experiences and any changes they notice during the trial. This could involve interviews or free recall sessions, especially if there are significant changes in consciousness or cognitive functions.

  5. Step 5

    End of trial

    At the conclusion of the trial, a final assessment will be conducted to gather comprehensive data on the participant's response to the medication.

    Participants will be informed about the findings related to their individual responses and any potential next steps or follow-up actions.

Who can join the trial?

19 criteria

  • Patients with Disorders of Consciousness (DoC):
    • Must be over 18 years old.
    • Must be more than 28 days after their injury.
    • Must have a diagnosis of UWS, MCS-, MCS+, or EMCS. These are different levels of consciousness disorders.
    • Must have stable vital signs, which means their basic body functions like heart rate and breathing are steady.
    • Must not have had any brain problems before their injury.
    • Must have a signed consent form. If the patient cannot give consent, their legal guardian must sign.
    • Will be observed for at least one week before the study starts to understand their usual health condition.
    • Neurotypical Volunteers:
      • Must be 18 years or older.
      • Must not have any mental or brain disorders at the time of joining the study.
      • Must be in good health.
      • Women who can become pregnant must have a negative pregnancy test before the study starts.
      • Women who can become pregnant and men who are sexually active with such women must agree to use birth control from 48 hours before the study starts until 24 hours after it ends.
      • Must have a signed consent form.
      • Patients with Vision Impairments:
        • Must be 18 years or older.
        • Must have partial or total vision impairments that happened after birth, confirmed by a specialist called a neuro-ophthalmologist.
        • Must not have any mental or brain disorders at the time of joining the study.
        • Women who can become pregnant must have a negative pregnancy test before the study starts.
        • Women who can become pregnant and men who are sexually active with such women must agree to use birth control from 48 hours before the study starts until 24 hours after it ends.
        • Must have a signed consent form.

Who cannot join the trial?

9 criteria

  • Patients who are not between the ages of 18 and 65.
  • Patients who are pregnant or breastfeeding.
  • Patients with a history of severe allergic reactions to the study medication.
  • Patients currently taking medications that might interfere with the study drug.
  • Patients with severe liver or kidney disease.
  • Patients with a history of drug or alcohol abuse.
  • Patients with certain psychiatric disorders that are not stable.
  • Patients who have participated in another clinical trial within the last 30 days.
  • Patients who are unable to comply with the study procedures.
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Investigated drugs

Zolpidem is a medication commonly used to help people with sleep problems, like insomnia, fall asleep more easily. In this clinical trial, researchers are exploring how zolpidem affects different groups of people, including those with consciousness disorders, vision impairments, and typical individuals. Interestingly, some people experience unexpected effects from zolpidem, such as improved consciousness or vision, or increased alertness and agitation instead of sleepiness. The study aims to understand why these surprising reactions happen and how zolpidem works differently in these individuals. This could help doctors provide better, personalized care for patients who respond to zolpidem in unusual ways.

What is already known about the treatment

Zolpidem – Zolpidem is typically administered orally in the form of tablets. It is currently being studied for its unique effects on patients with disorders of consciousness, those with vision impairments, and even healthy individuals. The main therapeutic use of zolpidem is to help with sleep problems, but in some cases, it has shown unexpected benefits, such as helping patients with consciousness disorders regain awareness or temporarily improving vision in those with impairments. At the molecular level, zolpidem works by enhancing the activity of a neurotransmitter called GABA, which helps calm the brain. It is classified as a sedative-hypnotic medication.

Investigated diseases

  • Acquired Vision Impairment

    Acquired vision impairment refers to a loss of vision that occurs after birth due to various causes such as injury, disease, or degenerative conditions. This condition can range from partial vision loss to complete blindness. The progression of vision impairment depends on the underlying cause. For instance, conditions like glaucoma or diabetic retinopathy may lead to gradual vision loss, while trauma can result in sudden impairment. Individuals with acquired vision impairment may experience difficulties in daily activities and require adaptations to maintain independence. The impact on vision can vary widely, affecting one or both eyes.

  • Disorders of Consciousness

    Disorders of consciousness encompass a range of conditions where there is a significant alteration in awareness and responsiveness. These include coma, vegetative state, and minimally conscious state. The progression of these disorders can vary, with some individuals showing signs of recovery over time, while others may remain in a prolonged state of reduced consciousness. Changes in consciousness levels can be influenced by the underlying cause, such as traumatic brain injury or severe illness. Patients may exhibit limited or no response to external stimuli, and their ability to communicate or interact with the environment is significantly impaired. The condition requires careful monitoring and assessment to understand any changes in consciousness levels.

Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IITrial ID2023-507404-31-03Estimated enrolment180 patientsSponsorUniversite De Liege

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).